Steam-valve



(No Model.) 2 Sheets-Sheet 1.

G. A. BOYDEN.

STEAM VALVE. No. 394,532. Patented Dec. 11, 1888.

Fig.1-

WITNESSES: INVENTOR:

A'rfoaNEY.

N PETERS. PholoLiXhognphar. Washington. a. c

(No Model.) 2 Sheets-Sheet 2.

G. A. BOYDEN.

STEAM VALVE.

No. 394,532. Patented Dec. 11, 1888.

Fig.2. 4

WITNESSES INVENTOR:

ATTO RNEY.

UNITED STATES PATENT OEEicE,

GEORGE A. BOYDEN, OF BALTIMORE, MARYLAND, ASSIGNOR TO THE BOY- DEN POVER BRAKE COMPANY OF BALTIMORE CITY, OF MARYLAND.

STEAM -VALVE.

SPECIFICATION forming part of Letters Patent No. 394,532, dated December 11, 1888.

Application filed August 10, 1888. Serial No. 282,396. (No model.)

To all whom it may concern: To control the admission or release of the Be it known that I, GEORGE A. BOYDEN, a steam on either side of the steam-piston 10, citizen of the United States, residing at Baltithe valve-chest 11 has therein the piston-valve more, in the State of Maryland, have invented 17, the heads of which are of differential 55 certain new and useful Improvements in areas, the valve-chest being provided at each Steam-Valves; andI do declare the following end with different bores, in which moves, re-

to be a full, clear, and exact description of the spectively, the larger head, 18, or the smaller invention, such as will enable others skilled in head, 19, of the said piston-valve, the said two the art to which it appertains to make and use heads being connected by the stem 20, the 6o 10 the same, reference being had to the accomsmaller head, 19, being placed at the bottom of panying drawings, and to the letters and figthe valve-chest, and each of the said pistonures of reference marked thereon, which form heads having therein the encircling exhausta part of this specification. recess 23 21, which communicates through a My invention relates to improvements in suitable chamber with the atmosphere, suit- 65 that class of steam-valves that are employed able packing-rings, 22, being placed around on steam-pumps and like engines of reciprothe piston-heads to render this recess 23 and eating movement, whereby steam is alterother parts stezun-tight. nately admitted or released from one side of As stated, the piston-valve 17 isto admit and the steam-piston or the other by the autorelease the steam on one side of the steam- 7o 20 matic movement of the valve without the aid piston 10 or the other, which is accomplished of an eccentric or any external valve-gearing; by the vertical movement of the piston-valve, and it consist-s of certain devices whereby whereby the ports 12 and 13 will be opened no dead-points will be permitted to the steamto the steam or to the exhaust recess 2. 2i. piston, and whereby the entire mechanism of As shown in Fig. 2, the steam-piston is at 25 the engine may be incased and protected half-stroke and the pistonvalve 17 centrally from dust and other exterior influences, all of over the openings 12 and 123, in consequence which I accomplish by the devices hereinafter of which all comn'iunication with the steamfully described and claimed, reference being cylinder is cut off. When steam is admitted had to the accompanying drawings, in which to the valve-chest through the opening 16, the 0 Figure 1 shows a side elevation of a vertipressure thereof will act upon the inner surcal air-pump in full. Fig. 2 shows a vertical faces of the piston-heads 1S and 19, and in section, somewhat enlarged, taken centrally consequence of the larger area of the upper through the steam-cylinder and steam-chest. head, 18, the piston-valve 17 will be moved The same figures refer to the same or simiupward past the opening 12, through which 3 5 lar parts throughout the several views. the steam will pass into the port H and exert The number 1 denotes a vertical steam airits pressure on top of the steam-piston 10, this pump, which is provided with this device, upward movement of thcpiston-valve 17 havthe steam-cylinder 5 and the wimp-cylinder ing caused the inner part of the lower or 6 thereof being connected by the tie-frame '7, smaller piston-head, 1.), to move in that di- 40 the piston-r0618, moving in the stut'fing-boxes rection past the port 13, and open commu- 9, being continuous and uniting the air-pump nication with the steam-port 15 and the expiston to the steam-piston 10, whereby they haust-recess 23 in the said piston-head, thus will be caused to move in unison. Attached releasing the pressure on the bottom side of to one side of the steam-cylinder is the cylinthe steam-piston 10, which will find escape to ,45 drical valve-chest 11, which is provided with the atmosphere through the exhaust-port 2]., suitable heads, and has therein the openings the reverse or downward movement of the 12 and 13, which communicate, through the piston-valve 17, by the devices which will steam-ports 14 and 15, with the interior of the shortly appear, causing the pressure to be adsteam cylinder, respectively, at either end mitted on the under side of the steam-piston I00 50 thereof, an opening, 16, serving to admit the through the opening 13 and the steam-port 15, live steam into the interior of the valve-chest. and released from the upper side thereof tion. Within the steam-cylinder casting are formed the auxiliary and independent ports 26 and 27, which, respectively, form a communication with the center of the valve-chest and the ends thereof, whereby pressure may be admitted or releasedby the auxiliary valve 28 to the outer chambers, 51 or 52, around the said piston-heads 18 and 19, and act upon the outer surfaces thereof, the said auxiliary valve 28 having therein the exhaust-ports 32 and 33, which operate with the auxiliary exhaustport 53 that is formed in the steam-cylinder casing, to release the pressure from one or the other side of the piston-valve 17. To impart movement to the auxiliary valve 28, whereby steam may be admitted or released from the outer sides of the piston-valve, a rod, 29, is passed through that part of the steamcylinder casting which forms the walls of the steam-ports thereof, the said rod being placed in the plane drawn through the axis of the steam-cylinder and the valve-chest, and free to be moved the required distance parallel with the movement of the steam-piston 10, this rod 29 being provided with a suitable collar, 30, which is straddled by the projecting arms 31 of the auxiliary valve 28, and which is free to be moved in the auxiliary exhaust-port 53, whereby the said rod 29 and the auxiliary valve 28 will be caused to move in unison and the said valve 28 caused to travel over the auxiliary ports 26 and 27, for the purpose described. To impart movement to the rod 29, there is provided on the ends thereof the tappets 34, which project sufficiently far into the cylinder to be touched and moved by the steam-piston 10, a suitable recess being formed in the cylinder-heads to permit this movement.

The manner of operating is as follows: In Fig. 2 the steam-piston is shown at halfstroke and the valves at mid-gear. Steam being admitted through the opening 16, the pressure will act upon the inner surfaces of the piston-heads 1S and 19, and in consequence of the greater area of the upper head, 18, the valve will be moved upward past the opening 12 and open the steam communication through the port 14 to the top of the steampiston, in consequence of which the steampiston 10 will move downward until it comes in contact with the lower tappet, 34, when the said tappet will be moved in unison therewith and cause the auxiliary valve 28 to be moved downward past'the port 26, through which steam will be admitted from the center of the valve-chest, therein pass around the upper piston-head, 18, into the chamber 51, and act upon the upper surface thereof, the downward movement of the auxiliary valve 28 having opened communication with the lower auxiliary port, 27, and the exhaustchamber 32 of the valve 28, through which the pressure from the lower side of the lower piston-head, 19, will be released and escape into the atmosphere through the exhaustopening 53; and in consequence of this unbalanced pressure on the piston-valve 17 it will be moved downward, the inner edge of the lower piston-head, 1f), moved past the opening 13, and steam will be admitted to the under side of the piston 10, and the steam on the upper side of the piston 10 released through the recess 24, which has been opened thereto by the downward movement of the said piston-valve 17, thus causing the pistonvalve 17 to be moved up or down by steampower as the steam-piston 10 comes in contact with the tappets 34 at either end of the steamcylinder.

From the construction of the device it will be seen that there are nodead-centers to the steam-piston and no point but from which the engine may be started when steam is admitted to the piston-valve 17, which, in consequence of the differential areas of the heads thereof, will always be moved upward when steam is first admitted thereto and cause the steam-piston to descend until in contact with the tappet 34, when the piston-valve will be reversed and the reciprocating movement made continuous.

Having described my invention and the manner of operating, what I claim, and desire to secure by United States Letters Patent, is

1. In combination with the cylinder 5 and main piston 10, the main valve 17 consisting of diiferential piston-heads 18 and 19, and the slide-valve 28, actuated by the movements of the main piston and arranged to alternately admit and release the steam-pressure to and from the outer surfaces of the main valve, for the purpose set forth.

2. In combination with the cylinder 5 and main piston 10, the main valve 17 consisting of differential piston-heads 18 and 19, and a slide-valve, 28, placed between the said piston-heads 18 and 19 and arranged to alternately admit and release the steam-pressure to and from the outer surfaces of the main valve, for the purpose set forth. I

3. In combination with the cylinder 5 and main piston 10, the main slide-valve 17 consisting of differential piston-heads 18 and 19, a slide-valve, 28, arranged to alternately admit and release the steam-pressure to and from the outer surfaces of the main valve, and a rod, 29, with tappets 34 thereon, for imparting movement to the said slide-valve 28, for the purpose set forth.

4. In combination with the cylinder 5 and main piston, the main valve 17, consisting of the differential heads 18 and 19, a valve-chainber in which moves the said main valve 17, and wherein are formed by the said main valve 17 a central and two outer chambers, ports connecting, respectively, the said central chamber with the two outer chambers,

for imparting movement to said main valve 17, the said rod 29 being placed between the said slide-valve 28 and the main piston 10 I 5 and operated by the said main piston, for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

GEORGE A. BOYDEN.

\Vitnesses:

WM. L. BAILIE, CHAs. I. HUGHSON. 

